US Patent 9550175 Honeycomb filter

A honeycomb filter includes a plurality of cells, porous cell walls, and an oxidation catalyst. The plurality of cells include exhaust gas introduction cells and exhaust gas emission cells. The oxidation catalyst is supported inside the porous cell walls in an amount of 5 to 60 g/L. The exhaust gas emission cells have an average cross sectional area larger than an average cross sectional area of the exhaust gas introduction cells in the cross section perpendicular to the longitudinal direction. A total volume of the exhaust gas introduction cells is larger than a total volume of the exhaust gas emission cells.